U.S. patent application number 12/028233 was filed with the patent office on 2008-12-25 for control device and control method for reduced power consumption in network device.
Invention is credited to Takayuki Muranaka, Yoshihiro Nakao, Atsushi Serizawa, Masayuki Shinohara.
Application Number | 20080320488 12/028233 |
Document ID | / |
Family ID | 40137861 |
Filed Date | 2008-12-25 |
United States Patent
Application |
20080320488 |
Kind Code |
A1 |
Nakao; Yoshihiro ; et
al. |
December 25, 2008 |
CONTROL DEVICE AND CONTROL METHOD FOR REDUCED POWER CONSUMPTION IN
NETWORK DEVICE
Abstract
This invention provides a data transfer control device for
carrying out data transfer using a plurality of transfer resources.
The data transfer control device comprises a transfer resource
management portion that set the plurality of transfer resources to
either one of a transfer-enabled state whereby data transfer is
enabled and a plurality of standby states on the basis of a load on
the data transfer control device and that manages the plurality of
transfer resources so as to assume the set operating status; and a
load distribution portion that distributes the data to transfer
resources that have been set to the transfer-enabled state. The
plurality of standby states are states which data transfer is
disabled and which mutually differ at a minimum in terms of at
least one of power consumption level and transition time to the
transfer-enabled state.
Inventors: |
Nakao; Yoshihiro; (Yokohama,
JP) ; Shinohara; Masayuki; (Kawasaki, JP) ;
Muranaka; Takayuki; (Kawasaki, JP) ; Serizawa;
Atsushi; (Minamiashigara, JP) |
Correspondence
Address: |
MATTINGLY, STANGER, MALUR & BRUNDIDGE, P.C.
1800 DIAGONAL ROAD, SUITE 370
ALEXANDRIA
VA
22314
US
|
Family ID: |
40137861 |
Appl. No.: |
12/028233 |
Filed: |
February 8, 2008 |
Current U.S.
Class: |
718/105 |
Current CPC
Class: |
H04L 67/1002 20130101;
G06F 1/3203 20130101; H04L 67/1017 20130101; Y02D 30/70 20200801;
H04W 52/0258 20130101; Y02D 70/00 20180101 |
Class at
Publication: |
718/105 |
International
Class: |
G06F 9/50 20060101
G06F009/50 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 25, 2007 |
JP |
2007-166550 |
Aug 27, 2007 |
JP |
2007-219185 |
Claims
1. A data transfer control device connected to a plurality of
circuits, for carrying out data transfer using a plurality of
transfer resources, comprising: a transfer resource management
portion that set the plurality of transfer resources to either one
of a transfer-enabled state whereby data transfer is enabled and a
plurality of standby states on the basis of a load on the data
transfer control device and that manages the plurality of transfer
resources so as to assume the set operating status; and a load
distribution portion that distributes the data to transfer
resources that have been set to the transfer-enabled state; wherein
the plurality of standby states are states which data transfer is
disabled and which mutually differ at a minimum in terms of at
least one of power consumption level and transition time to the
transfer-enabled state.
2. The data transfer control device according to claim 1 wherein
the plurality of standby states includes at least two standby
states in which the transition time is longer the lower the power
consumption level.
3. The data transfer control device according to claim 1 wherein
management of the transfer resources additionally involves
measuring a load on each individual circuit of the data transfer
control device, and managing the plurality of transfer resources on
the basis of the total load measured on all circuits.
4. The data transfer control device according to claim 1 wherein
the transfer resource management portion additionally predicts
fluctuation of a load and carries out management of the plurality
of transfer resources on the basis of the predicted
fluctuation.
5. The data transfer control device according to claim 4 wherein
management of the transfer resources additionally involves
calculating a sum of the linkup speeds of all circuits of the data
transfer control device; predicting fluctuation of load using the
calculated sum of the linkup speeds of all circuits as an upper
limit; and carrying out management of the plurality of transfer
resources on the basis of the predicted fluctuation.
6. The data transfer control device according to claim 1 wherein
management of the transfer resources additionally involves
predicting fluctuation of the load on each individual circuit of
the data transfer control device, and managing the plurality of
transfer resources on the basis of the predicted total load on all
circuits.
7. The data transfer control device according to claim 4 wherein
the transfer resource management portion additionally stores load
prediction information predicted in advance and relating to future
load fluctuation, and carries out the prediction on the basis of
the load prediction information.
8. The data transfer control device according to claim 4 wherein
the transfer resource management portion additionally carries out
prediction on the basis of cyclical nature of the load.
9. The data transfer control device according to claim 8 wherein
management of the plurality of transfer resources on the basis of
the predicted fluctuation additionally involves prediction of
fluctuation of the load in relation to at least one specific
period, and management of at least one specific standby state among
the plurality of standby states on the basis of predicted
fluctuation of load in the specific period.
10. The data transfer control device according to claim 8 wherein
management of the plurality of transfer resources on the basis of
the predicted fluctuation additionally involves predicting
fluctuation of the load in relation to a plurality of specific
periods; and associating individual fluctuations of the load with
individual transitions of a plurality of specific standby states
among the plurality of standby states on the basis of load
fluctuation predicted for each of the plurality of specific
periods; and wherein the associations are made such that specific
periods of longer period correspond to standby states for which the
power consumption is lower.
11. The data transfer control device according to claim 10 wherein
data transfer control device carries out data transfer through a
plurality of communication data classes having been pre-classified
into a plurality of types, and management of the plurality of
transfer resources on the basis of the predicted fluctuation
additionally involves predicting fluctuation of the load in at
least one type of specific communication data class among the
plurality of types of communication data class in relation to a
plurality of specific periods; and associating individual
fluctuations of the load with individual transitions of a plurality
of specific standby states among the plurality of standby states on
the basis of load fluctuation predicted for each of the plurality
of specific periods in the specific communication data class.
12. The data transfer control device according to claim 1 wherein
the data transfer control device carries out data transfer through
a plurality of communication data classes having been
pre-classified into a plurality of types, each of the plurality
transfer resources in the transfer-enabled state is assigned any of
the plurality of types of communication data class; the transfer
resource management portion additionally manages the transfer
resources for each of the plurality of types of communication data
class on the basis of load fluctuation for each of the plurality of
types of communication data class; and the load distribution
portion additionally analyzes which of the plurality of types of
communication data class is being used to communicate the data, and
distributes the data by distributing the analyzed data to transfer
resources assigned to the same communication data class as the
analyzed data.
13. The data transfer control device according to claim 12 wherein
management of the transfer resources additionally involves
measuring load fluctuation in at least one specific communication
data class among a plurality of communication data classes, in each
circuit of the data transfer control device; and managing the
plurality of transfer resources on the basis of the total load of
all of the measured circuits.
14. The data transfer control device according to claim 12 wherein
management of the transfer resources additionally involves
predicting load fluctuation in at least one type of specific
communication data class among the plurality of types of
communication data class, and managing the plurality of transfer
resources on the basis of the predicted fluctuation.
15. The data transfer control device according to claim 12 wherein
management of the transfer resources additionally involves
predicting load fluctuation in at least one specific communication
data class among a plurality of communication data classes, in each
circuit of the data transfer control device; and managing the
plurality of transfer resources on the basis of the predicted
fluctuation.
16. The data transfer control device according to claim 14 wherein
the transfer resource management portion additionally stores load
prediction information predicted in advance and relating to future
load fluctuation, and carries out the prediction on the basis of
the load prediction information.
17. The data transfer control device according to claim 14 wherein
the transfer resource management portion additionally carries out
the prediction on the basis of cyclical nature of the load.
18. The data transfer control device according to claim 17 wherein
management of the plurality of transfer resources additionally
involves predicting load fluctuation in the specific communication
data class in relation to at least one specific period; and on the
basis of the predicted load fluctuation in the specific
communication data class in the specific period, managing
transition among at least one specific standby state among the
plurality of standby states and transfer resources in the
transfer-enabled state which have been assigned to the specific
communication data class.
19. The data transfer control device according to claim 1 wherein
the plurality of standby states includes a suspended operation
state in which the supply of power is suspended; and during
transition to the transfer-enabled state of a transfer resource in
an operating state which is one of the plurality of standby states
except for the suspended operation state, the transfer resource
management portion additionally carries out transition of a
transfer resource in the suspended operation state to the state of
the transitioned transfer resource prior to the transition.
20. A network transfer system for transferring data in a network,
comprising: a circuit interface portion connected to a network
circuit, for transmitting and receiving the data; a plurality of
transfer resources for carrying out transfer processing of the
data; and the data transfer control device according to claim
1.
21. A data transfer control method for carrying out data transfer
using a plurality of transfer resources, comprising the steps of:
setting the plurality of transfer resources to either one of a
transfer-enabled state whereby data transfer is enabled and a
plurality of standby states on the basis of a load on the data
transfer control device; managing the plurality of transfer
resources so as to assume the set operating status; and
distributing data to transfer resources that have been set to the
transfer-enabled state; wherein the plurality of standby states are
states which data transfer is disabled and which mutually differ at
a minimum in terms of at least one of power consumption level and
transition time to the transfer-enabled state.
Description
CLAIM OF PRIORITY
[0001] The present application claims priority from Japanese
applications P2007-166550A filed on Jun. 25, 2007 and P2007-219185A
filed on Aug. 27, 2007, the content of which is hereby incorporated
by reference into this application.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The present invention relates to technology for carrying out
transfer of data in a network.
[0004] 2. Description of the Related Art
[0005] Network devices that use multiple transfer resources in
order to perform data transfer have come to be used for
applications such as IX and company internal networks. In such
network devices, past practice has been to use all of the transfer
resources irrespective of the level of traffic. The related art is
disclosed in the applications JP-A-P2004-135106A and
JP-A-pP2000-201166A
[0006] However, as there is substantially no drop in power
consumption by transfer resources in association with the lower
data transfer levels, some of the power consumed during times of
low traffic at certain times of day or certain seasons will be
wasted. This problem is not just one relating to traffic
fluctuations associated with certain times of day, but rather one
relating to the general versatility of network devices with respect
to traffic requests. Specifically, it has proven difficult to
provide a network device able to operate at appropriate power
levels depending on traffic requests. By way of a specific example,
providing network devices of differing processing capabilities and
power consumption for high-load applications such as IX (Internet
eXchange) and for relatively low-load applications was associated
with increased administration costs and hardware costs.
SUMMARY
[0007] With a view to addressing the problem outlined above, it is
an object of the present invention to provide technology for
reducing power consumption with substantially no drop in transfer
capability during data transfer carried out through transfer of
data using multiple transfer resources.
[0008] One aspect of the present invention provides a data transfer
control device for carrying out data transfer using a plurality of
transfer resources. A data transfer control device connected to a
plurality of circuits, comprising:
[0009] a transfer resource management portion that set the
plurality of transfer resources to either one of a transfer-enabled
state whereby data transfer is enabled and a plurality of standby
states on the basis of a load on the data transfer control device
and that manages the plurality of transfer resources so as to
assume the set operating status; and
[0010] a load distribution portion that distributes the data to
transfer resources that have been set to the transfer-enabled
state;
[0011] wherein the plurality of standby states are states which
data transfer is disabled and which mutually differ at a minimum in
terms of at least one of power consumption level and transition
time to the transfer-enabled state.
[0012] In the data transfer control device of the present
invention, the operating status of the plurality of transfer
resources is managed on the basis of the load on the data transfer
control device so that the operating status thereof assumes a
transfer-enabled state whereby data transfer is enabled, or any of
a plurality of standby states which mutually differ in terms of
power consumption level and/or transition time to the
transfer-enabled state. Consequently, in response to load
fluctuations the device can utilize any of standby states which
mutually differ in terms of power consumption level and/or
transition time. Both rapid response to load fluctuations and
reduced power consumption can be achieved thereby.
[0013] In the aforementioned data transfer control device,
[0014] the plurality of standby states may include two standby
states in which the transition time is longer the lower the power
consumption level.
[0015] In the aforementioned data transfer control device,
[0016] the transfer resource management portion may additionally
predict fluctuation of the load and carry out management of the
plurality of transfer resources on the basis of the predicted
fluctuation.
[0017] In the aforementioned data transfer control device,
[0018] management of the transfer resources may additionally
involve predicting fluctuation of the load on each individual
circuit of the data transfer control device, and managing the
plurality of transfer resources on the basis of the predicted total
load on all circuits. For example, since the cyclical nature of
communication will differ between some kinds of communication and
enterprise data communication in which transfer levels increase
during specific time periods, a higher degree of accuracy in
management can be achieved by enhancing the accuracy of prediction.
Additionally, it is conceivable that differences in data
communication characteristics may arise due to time differences
between individual regions, and so on.
[0019] In the aforementioned data transfer control device,
[0020] the transfer resource management portion may additionally
store load prediction information predicted in advance and relating
to future load fluctuation, and carry out the prediction on the
basis of the load prediction information. For example, it would be
possible to make a prediction on the basis of an increase in load
due to a non-regular event such as the World Cup or the opening of
the high school baseball season (opening day is different each
year), for which it is difficult to predict increased load based on
periodic nature (season) alone, but which is nevertheless a
scheduled event that is known in advance. In this way, fluctuations
in load may be predicted on the basis of information representing
predicted load fluctuations that have been predicted in advance
outside the network transfer system (discussed later).
[0021] Specifically, a management server (discussed later) may be
provided with a memory area, not shown, having an event calendar
(load prediction information) stored therein; and load may be
predicted on the basis of this event calendar. The present
invention is applicable to instances in which load is predicted by
any of various methods: for example it would be acceptable to
predict load fluctuations on the basis of the rate of change of
load; or to compile a database of load fluctuation patterns and to
activate extra transfer resources in response to detection of an
unknown fluctuation pattern.
[0022] In the aforementioned data transfer control device,
[0023] the transfer resource management portion may additionally
carry out prediction on the basis of cyclical nature of the
load.
[0024] The amount of data transfer has a cyclical characteristic
owing to its intimate relationship with human activity which is
cyclical in nature. With this configuration, fluctuations in load
can be predicted on the basis of this cyclical nature, so multiple
transfer resources can be managed appropriately. As a result, it is
possible to respond more appropriately to load fluctuations, and to
minimize transfer volume margins for multiple transfer resources.
"Cyclical nature" herein refers to a phenomenon that includes at
least the characteristic of phase (relationship to time) or of
period (inverse of frequency), or both.
[0025] In the aforementioned data transfer control device,
[0026] management of the plurality of transfer resources on the
basis of the predicted fluctuation may additionally involve
predicting fluctuation of the load in relation to at least one
specific period, and managing at least one specific standby state
among the plurality of standby states on the basis of predicted
fluctuation of load in the specific period.
[0027] By managing a specific standby state on the basis of
fluctuation of load in a specific period in this way, it is
possible to achieve fine-tuned control with consideration to the
cyclical nature of data transfer volume.
[0028] In the aforementioned data transfer control device,
[0029] management of the plurality of transfer resources on the
basis of the predicted fluctuation may additionally involve
predicting fluctuation of the load in relation to a plurality of
specific periods; and associating individual fluctuations of the
load with individual transitions of a plurality of specific standby
states among the plurality of standby states, on the basis of load
fluctuation predicted for each of the plurality of specific
periods; and
[0030] the associations may be made such that specific periods of
longer period correspond to standby states for which the power
consumption is lower and the transition time is longer.
[0031] Through management involving association in this way such
that specific periods of longer period correspond to standby states
for which the power consumption is lower and the transition time is
longer, it is possible for example to bring about transition from a
standby state having a long transition time in response to a load
fluctuation having a relatively long period or to bring about
transition from a standby state having a short transition time in
response to a load fluctuation having a relatively short period, so
that response to load fluctuations can be improved.
[0032] In the aforementioned data transfer control device,
[0033] the data transfer control device may carry out data transfer
through a plurality of communication data classes (communication
classified by a specific rule) having been pre-classified into a
plurality of types,
[0034] and management of the plurality of transfer resources on the
basis of the predicted fluctuation may additionally involve
predicting fluctuation of the load in at least one type of specific
communication data class among the plurality of types of
communication data class in relation to a plurality of specific
periods; and associating individual fluctuations of the load with
individual transitions of a plurality of specific standby states
among the plurality of standby states on the basis of load
fluctuation predicted for each of the plurality of specific periods
in the specific communication data class.
[0035] Thus, since for example the cyclical nature of communication
differs between data communication by telephone, in which transfer
levels increase during specific time periods, and other kinds of
communication, a higher degree of accuracy in management can be
achieved by enhancing the accuracy of prediction.
[0036] In the aforementioned data transfer control device,
[0037] the data transfer control device may carry out data transfer
through a plurality of communication data classes having been
pre-classified into a plurality of types,
[0038] each of the plurality transfer resources in the
transfer-enabled state may be assigned any of the plurality of
types of communication data class;
[0039] the transfer resource management portion may additionally
manage the transfer resources for each of the plurality of types of
communication data class, on the basis of load fluctuation for each
of the plurality of types of communication data class; and
[0040] the load distribution portion may additionally analyze which
of the plurality of types of communication data class is being used
to communicate the data, and distribute the data by distributing
the analyzed data to transfer resources assigned to the same
communication data class as the analyzed data. The data transfer
control device can narrow down the communication data classes
targeted for processing by the transfer resources, thereby
achieving reduced power consumption, as well as greater process
efficiency and stability.
[0041] In the aforementioned data transfer control device,
[0042] management of the transfer resources may additionally
involve predicting load fluctuation in at least one type of
specific communication data class among the plurality of types of
communication data class, and managing the plurality of transfer
resources on the basis of the predicted fluctuation.
[0043] In the aforementioned data transfer control device,
[0044] the transfer resource management portion may additionally
store load prediction information predicted in advance and relating
to future load fluctuation, and carry out the prediction on the
basis of the load prediction information; or
[0045] the transfer resource management portion may additionally
carry out prediction on the basis of cyclical nature of the
load.
[0046] Where transitions of specific standby states are managed on
the basis of predicted load fluctuations in specific communication
data classes in this way, is possible to achieve fine-tuned control
with consideration to predicted future fluctuations of data
transfer volume in specific communication data classes (e.g. data
communication by telephone in which transfer volume increases for a
specific time period) and to differences in the importance
thereof.
[0047] In the aforementioned data transfer control device,
[0048] management of the plurality of transfer resources may
additionally involve predicting load fluctuation in the specific
communication data class in relation to at least one specific
period; and on the basis of the predicted load fluctuation in the
specific communication data class in the specific period, managing
transition among at least one specific standby state among the
plurality of standby states and transfer resources in the
transfer-enabled state which have been assigned to the specific
communication data class.
[0049] In the aforementioned data transfer control device,
[0050] the plurality of standby states may include a suspended
operation state in which the supply of power is suspended
[0051] and during transition to the transfer-enabled state of a
transfer resource in an operating state which is one of the
plurality of standby states except for the suspended operation
state, the transfer resource management portion may additionally
carry out transition of the transfer resource in the suspended
operation state to the state of the transitioned transfer resource
prior to the transition.
[0052] Since the reduction in the number of transfer resources in
operating states except for the suspended operation state in which
the supply of power is suspended can be suppressed when transfer
resources are transitioned to the transfer-enabled state due to an
increase in load, the above data transfer control device suppresses
a drop in responsiveness caused by transition to the
transfer-enabled state in response to a load fluctuation.
[0053] The present invention further provides a network transfer
system for transferring data in a network. This network transfer
system comprises
[0054] a circuit interface portion connected to a network circuit,
for transmitting and receiving the data;
[0055] a plurality of transfer resources for carrying out transfer
processing of the data; and
[0056] any of the data transfer control devices set forth
hereinabove.
[0057] The present invention further provides a data transfer
control method for carrying out data transfer using a plurality of
transfer resources. This network transfer method comprises the
steps of
[0058] on the basis of the load on the data transfer control
device, setting the operating status of the plurality of transfer
resources to a transfer-enabled state whereby data transfer is
enabled, or to any of a plurality of standby states whereby data
transfer is disabled and which mutually differ at a minimum in
terms of at least one of power consumption level and transition
time to the transfer-enabled state; and managing the plurality of
transfer resources so as to assume the set operating status;
and
[0059] distributing the data to transfer resources that have been
set to the transfer-enabled state.
[0060] The present invention is not limited to the embodiments set
forth above and may also be reduced to practice as a network
transfer method. Furthermore there are various other possible
embodiments as well, such as embodiment as a computer program for
building such a method or device or as a recording medium having
such a computer program recorded thereon.
BRIEF DESCRIPTION OF THE DRAWINGS
[0061] FIG. 1 is a block diagram depicting an overview of a network
transfer system 100 in Embodiment 1 of the present invention;
[0062] FIG. 2 is a block diagram depicting a circuit card 112 as an
implementation example of Embodiment 1;
[0063] FIG. 3 is an illustration showing the concept of management
status of multiple transfer resources;
[0064] FIG. 4 is a timing chart depicting an example of temporal
fluctuations in the number of retrieval/transfer portions 130
placed in the transfer-enabled state Act in a simple threshold
value mode;
[0065] FIG. 5 is a flowchart depicting a transfer resource
management process routine in simple threshold value mode;
[0066] FIG. 6 is a timing chart depicting another example of
temporal fluctuation of the transfer-enabled number Na in
hysteresis mode;
[0067] FIG. 7 is a flowchart depicting a transfer resource
management process routine in hysteresis mode;
[0068] FIG. 8 is a flowchart depicting a transfer-enabled number
decrease process routine (Step S410);
[0069] FIG. 9 is a flowchart depicting a transfer-enabled number
increase process routine (Step S420);
[0070] FIG. 10 is a timing chart depicting an example of
statistical fluctuation of traffic load in a network transfer
system 100 in Embodiment 2 of the present invention;
[0071] FIG. 11 is a spectrum diagram depicting an example of
statistical fluctuation of traffic load in the network transfer
system 100, shown by a frequency domain;
[0072] FIG. 12 is a flowchart showing a routine of a transfer
resource management process (Step Slob) of Embodiment 2 of the
present invention;
[0073] FIG. 13 is an illustration showing relationship of steps to
transition targets in the transfer resource management of
Embodiment 2;
[0074] FIG. 14 is a block diagram showing a data transfer control
device that uses switch LSI's;
[0075] FIG. 15 is a block diagram showing a clustering
configuration built from multiple data transfer control devices (or
communication devices) connected via a network;
[0076] FIG. 16 is a block diagram showing a shared database type
clustering system;
[0077] FIG. 17 is a block diagram showing an independent database
type clustering system;
[0078] FIG. 18 is a block diagram showing a configuration in which
the plurality of standby states do not include a suspended
operation state STBYn;
[0079] FIG. 19 is a block diagram showing a data transfer control
device in which link aggregation is implemented; and
[0080] FIG. 20 is a block diagram showing a configuration in which
data is distributed according to the individual communication data
classes, distributing only the load of a single communication data
class to the transfer resources.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A. Network Transfer System of Embodiment 1 of the Present
Invention
[0081] Certain specific preferred embodiments of the present
invention will be described below. FIG. 1 is a block diagram
depicting an overview of a network transfer system 100 in a first
embodiment of the present invention. The network transfer system
100 includes five circuit interface portions 102, three
retrieval/transfer portions 130, five load distribution portions
104, and a management server 101 for controlling these. Control of
the circuit interface portions 102 and the retrieval/transfer
portions 130 by the management server 101 may take place via the
load distribution portions 104 as depicted in FIG. 1; or a
configuration involving direct control may be employed.
[0082] The circuit interface portions 102 are connected to a
plurality of external network circuits, not shown; they execute
physical layer processes such as shaping electrical signals for
sending and receiving frame data, as well as the process of
multiplexing the circuits (e.g. through time division or frequency
division). From the header information in the frame data, the
retrieve/transfer portions 130 determine the frame transfer
destination port of the network transfer system 100, and transfer
the frame data. The load distribution portions 104 distribute the
transfer process among each of the three retrieval/transfer
portions 130 on the basis of instructions from the management
server 101 and the load on each of the retrieval/transfer portions
130. This distribution will be discussed in detail later.
[0083] The five circuit interface portions 102 are connected to
each of the three retrieval/transfer portions 130 via all five of
the load distribution portions 104 (FIG. 1). In other words, each
of the five circuit interface portions 102 connected in the
bidirectional way with the external network circuits is able to
connect to any of retrieval/transfer portions 130 via the load
distribution portions 104 each connected therewith.
[0084] The retrieval/transfer portions 130 and the management
server 101 correspond respectively to the "transfer resources" and
"transfer resource management portion" recited in the claims. In
the present embodiment, the network transfer system 100 employs
circuit interface portions 102 capable of both transmitting and
receiving; however, a configuration having a circuit interface
portion for receiving (not shown) and a different circuit interface
portion for transmitting (not shown) would be acceptable as well.
In such a configuration, these portions could be constituted either
as an integrated unit or as separate components.
[0085] FIG. 2 is a block diagram depicting a circuit card 112 as an
implementation example of the first embodiment. the circuit card
112 includes the circuit interface portion 102, the load
distribution portion 104, and a sequence assurance portion 106. The
sequence assurance portion 106 sorts the data sequence so that the
sequence of multiple frame data input from the retrieval/transfer
portion 130 matches the correct original sequence, and outputs the
data to the circuit interface portion 102.
[0086] The load distribution portion 104 includes a distribution
portion 107 for distributing frame data to each of the three
retrieval/transfer portions 130, and an assignment portion 105 for
presenting the distribution portion 107 with assignment
notification data instructing the distribution destinations.
[0087] There are various possible frame data distribution formats
for the distribution portion 107, such the hash format whereby the
sequence of frame data can be assured through analysis; and the
round-robin format whereby the sequence of frame data cannot be
assured. Where only the hash format or other format which assures
the sequence of frame data is used as the frame data distribution
format by the load distribution portion 104, the sequence assurance
portion 106 may be omitted.
[0088] The assignment portion 105 generates assignment notification
data on the basis of status data provided by the management server
101 and load information provided by the three retrieval/transfer
portions 130. The status information will include operating status
of each of the retrieval/transfer portions 130, i.e. information
representing whether it is in the transfer-enabled state or any of
the standby states (transfer-disabled states). The load information
will include information representing load conditions of each of
the three retrieval/transfer portions 130. Determinations of
distribution destination may be made, for example, by having the
assignment portion 105 identify at least one transfer-enabled
retrieval/transfer portion 130 on the basis of the status
information; and from among the identified retrieval/transfer
portions 130 select that with the lowest transfer load, on the
basis of the load information.
[0089] The load information may also include information
representing load information for each of the circuits belonging to
the plurality of circuit interfaces (the five circuit interface
portions 102).
[0090] FIG. 3 is an illustration showing the concept of management
status of multiple transfer resources. In Embodiment 1, the
transfer resources correspond to the retrieval/transfer portions
130. Operating status St1 of the multiple transfer resources is
divided into a transfer-enabled state Act and several standby
states STBY1 through STBYn which represent transfer-disabled
states. The standby states are in turn divided into a first through
n-th standby state STBY1 through STBYn which differ from one
another in terms of transition time to the transfer-enabled state,
and power consumption. In this example, a first standby state
STBY1, a second standby state STBY2, and a third standby state
STBY3 respectively represent a reduced clock frequency state, a
reduced clock frequency/reduced voltage state, and a suspended
operation state.
[0091] As will be apparent from the graph Gr1, the first standby
state STBY1, the second standby state STBY2, and the third standby
state STBY3 differ from one another in terms of transition time to
the transfer-enabled state Act and in power consumption.
Specifically, the first standby state STBY1 is the standby state
with the shortest transition time to the transfer-enabled state Act
and the largest power consumption. The second standby state STBY2
is a standby state with a longer transition time to the
transfer-enabled state Act than first standby state STBY1, but
lower power consumption than the first standby state STBY1.
[0092] It is possible to establish any number of these standby
states between the transfer-enabled state Act and the suspended
operation state STBYn. For example, it would be possible to utilize
a drop in voltage produced by stopping various circuits, i.e. the
interface circuit with an external memory, not shown, or a SERDES
(SERializer/DESerializer), or by a voltage margin resulting for
example from a drop in clock frequency or from a temperature drop
during a period of low load, in order to achieve lower power
consumption in the standby states. However, where a voltage margin
caused by a temperature drop is utilized, it will be preferable to
estimate the voltage margin on the basis of actual temperature
measurement.
[0093] FIG. 4 is a timing chart depicting an example of temporal
fluctuations in the number of retrieval/transfer portions 130
placed in the transfer-enabled state Act in a simple threshold
value mode. In this example, the number of retrieval/transfer
portions 130 to be placed in the transfer-enabled state Act will be
determined by a feedback format depending on the load (traffic
load) on the network transfer system 100, using two threshold
values Th1_2 and Th2_3.
[0094] FIG. 5 is a flowchart depicting a transfer resource
management process routine in simple threshold value mode. In Step
S100, the management server 101 will perform load measurement of
traffic load. Load measurement can be carried out, for example, by
computing total frame data transfer volume for the multiple
transfer resources (the three retrieval/transfer portions 130). In
Step S200, the management server 101 will decide whether the
measured load exceeds the preset threshold value Th1_2. If the load
is smaller than the threshold value Th1_2, the multiple transfer
resources will be controlled such that the number of
retrieval/transfer portions 130 placed in the transfer-enabled
state Act equals 1. On the other hand, if the load exceeds the
threshold value Th1_2, the process will advance to Step S300.
[0095] Load measurement may also be carried out by computing total
frame data transfer volume for the circuits belonging to the
multiple circuit interfaces (the five circuit interface portions
102).
[0096] In Step S300, the management server 101 will decide whether
the measured load exceeds the preset threshold value Th2_3. If the
load is smaller than the threshold value Th2_3, the multiple
transfer resources will be controlled such that the
transfer-enabled number Na equals 2 (Step S310). On the other hand,
if the load exceeds the threshold value Th2_3, the multiple
transfer resources will be controlled such that the
transfer-enabled number Na equals 3 (Step S320). This process is
carried out at a prescribed cycle (e.g. every one second), so that
the number of retrieval/transfer portions 130 placed in the
transfer-enabled state Act will fluctuate depending on traffic
load.
[0097] FIG. 6 is a timing chart depicting another example of
temporal fluctuation of the transfer-enabled number Na in
hysteresis mode. In this example, fluctuations of the
transfer-enabled number Na are suppressed through hysteresis in
addition to the feedback format mentioned above. This kind of
hysteresis is accomplished using four threshold values Th1_2u,
Th2_3u, Th2_1d, and Th3_2d.
[0098] FIG. 7 is a flowchart depicting a transfer resource
management process routine in hysteresis mode. In Step S100 load
measurement of traffic load is performed in the same way as in
simple threshold value mode. In Step 400, the management server 101
will decide whether the load in increasing or decreasing. This
decision can be made, for example, by storing a data time series
representing the load, and making reference to this. If as a result
of the decision it is decided that the load is decreasing, the
process will advance to a transfer-enabled number decrease process
(Step S410), whereas if it is decided that the load is increasing,
the process will advance to a transfer-enabled number increase
process (Step S420).
[0099] FIG. 8 is a flowchart depicting the transfer-enabled number
decrease process routine (Step S410). In Step S411, the management
server 101 will decide whether the load is greater than a preset
threshold value Th2_1d for use in the transfer-enabled number
decrease process. If the result of this decision is that the load
is smaller than the threshold value Th2_1d, the transfer resources
will be controlled such that the transfer-enabled number Na equals
1 (Step S412), whereas if the load is greater than the threshold
value Th2_1d, the process will advance to Step S413.
[0100] In Step S413, the management server 101 will decide whether
the load is greater than a preset threshold value Th3_2d for use in
the transfer-enabled number decrease process. If the result of this
decision is that the load is smaller than the threshold value
Th3_2d, the transfer resources will be controlled such that the
transfer-enabled number Na equals 2 (Step S414), whereas if the
load is greater than the threshold value Th3_2d, the transfer
resources will be controlled such that the transfer-enabled number
Na equals 3 (Step S415).
[0101] FIG. 9 is a flowchart depicting the transfer-enabled number
increase process routine (Step S420). In Step S421, the management
server 101 will decide whether the load is greater than a preset
threshold value Th1_2u for use in the transfer-enabled number
increase process. If the result of this decision is that the load
is smaller than the threshold value Th1_2u, the transfer resources
will be controlled such that the transfer-enabled number Na equals
1 (Step S422), whereas if the load is greater than the threshold
value Th1_2u, the process will advance to Step S423.
[0102] In Step S423, the management server 101 will decide whether
the load is greater than a preset threshold value Th2_3u for use in
the transfer-enabled number increase process. If the result of this
decision is that the load is smaller than the threshold value
Th2_3u, the transfer resources will be controlled such that the
transfer-enabled number Na equals 2 (Step S424), whereas if the
load is greater than the threshold value Th2_3u, the transfer
resources will be controlled such that the transfer-enabled number
Na equals 3 (Step S425).
[0103] In Embodiment 1, since the number of retrieval/transfer
portions 130 placed in the transfer-enabled state Act can be varied
appropriately depending on the traffic load in this way, the amount
of power consumed in data transfer when transferring data using
multiple transfer resources can be reduced. The term "cyclical
nature" herein is used to include at least the characteristic of
phase (relationship to time, e.g. day or night) or of period
(inverse of frequency), or both.
[0104] In Embodiment 1 of the present invention, the management
server 101 may also control the transfer resources using as the
upper limit the total spectrum of the data transfer control device,
this total spectrum of active circuits having been calculated from
the linkup state in all of the circuits of the data transfer
control device. In a transfer process of the total spectrum of
active circuits, in the event it is not necessary to use all of the
transfer resources at least one or more of the transfer resources
can be transitioned to the standby state with the lowest power
consumption. For example, when the total spectrum of active
circuits is smaller than the threshold value Th2_3, a maximum
transfer-enabled number Na of 2 will suffice, and control will be
carried out so that three resources never assume the
transfer-enabled state simultaneously. At this time, at least one
transfer resource can be transitioned to the standby state with the
lowest power consumption.
B. Network Transfer System of Embodiment 2 of the Present
Invention
[0105] FIG. 10 is a timing chart depicting an example of
statistical fluctuation of traffic load in the network transfer
system 100 in a second embodiment of the present invention. In this
example, the sampling window is equivalent to one year. In FIG. 10
are shown time-series statistical data STR for traffic load,
high-frequency component data STH derived by extracting the
high-frequency component from the statistical data STR,
medium-frequency component data STM derived by extracting the
medium-frequency component, and low-frequency component data STL
derived by extracting the low-frequency component.
[0106] FIG. 11 is a spectrum diagram depicting an example of
statistical fluctuation of traffic load in the network transfer
system 100, shown by a frequency domain. In this example, peaks are
observed in a low-frequency band FL, a medium-frequency band FM,
and a high-frequency band FH. In this example, such peaks are
manifested as fluctuations with a daily cycle (e.g. a high load
time slot and a low load time slot), fluctuations with a monthly
cycle (e.g. high load at month end or the like, and fluctuations
with a yearly cycle (e.g. high load at the turn of the year or at
fiscal year end). The inventors created the following control rule
based on the discovery that such spectral characteristics are
utilizable for more efficient transitioning between the
transfer-enabled state Act and multiple standby states STBY1
through STBYn having mutually different transition times to the
transfer-enabled state and power consumption levels.
[0107] FIG. 12 is a flowchart showing a routine of a transfer
resource management process (Step S10b) of Embodiment 2. FIG. 13 is
an illustration showing relationship of steps to transition targets
in the transfer resource management of Embodiment 2. In Step S100,
traffic load is measured in the same way as in Embodiment 1. In
Step S500, the management server 101 decides whether the traffic
load exhibits large fluctuations with a long cycle (low
frequency).
[0108] This decision can be made, for example, by using a filter of
a center frequency FL (FIG. 11) prepared in advance to extract the
low-frequency component from a time series of data for past traffic
load for a prescribed time period; and on the basis of this
extracted data determining whether the calculated fluctuation level
per unit of time is greater than a prescribed value (or whether it
is close to halfway between peaks and valleys of the waveform). If
the result of the decision is that large fluctuations appear at a
long cycle (sufficiently close to halfway between peaks and valleys
of the waveform), after executing transition of the transfer
resources between the transfer-enabled state Act and the standby
state STBYn having the longest transition time until transfer is
enabled (Step S510) in the same way as in Embodiment 1, the process
will advance to Step S600. On the other hand, if decision is that
large fluctuations do not appear at a long cycle, the process will
advance directly to Step S600.
[0109] In Step S600, the management server 101 decides whether the
traffic load exhibits large fluctuations with a medium cycle
(medium frequency). This decision can be made by using a filter of
a center frequency FM (FIG. 11) prepared in advance to extract the
medium-frequency component from a time series of data for traffic
load; and on the basis of this extracted data determining whether
the calculated fluctuation level per unit of time is greater than a
prescribed value. If the result of the decision is that large
fluctuations appear at a medium cycle, after executing transition
of the transfer resources between the standby state STBY2 and the
transfer-enabled state Act (Step S610) in the same manner as in
Embodiment 1, the process will advance to Step S700.
[0110] During this transition, it is preferable to carry out
transition between the standby state STBY2 and the standby state
STBYn in conjunction to suppress fluctuation of the number of
transfer resources that have assumed the standby state STBY2. The
reason for doing so is to avoid a decline in responsiveness of the
network transfer system 100 due to load fluctuations that can be
caused by transitions in response to fluctuating load. On the other
hand, if decision is that large fluctuations do not appear at a
medium cycle, the process will advance directly to Step S700.
[0111] In Step S700, the management server 101 decides whether the
traffic load exhibits large fluctuations with a short cycle (high
frequency). This decision can be made by using a filter of a center
frequency FH (FIG. 11) prepared in advance to extract the
high-frequency component from a time series of data for traffic
load; and on the basis of this extracted data determining whether
the calculated fluctuation level per unit of time is greater than a
prescribed value. If the result of the decision is that large
fluctuations appear at a short cycle, transition of the transfer
resources between the standby state STBY1 and the transfer-enabled
state Act (Step S710) in the same manner as in Embodiment 1, the
process will be executed (Step S710). During this transition, since
the number of transfer resources in the standby state STBY1 will
increase or decrease, it will be preferable to suppress fluctuation
of the number of transfer resources in the standby state STBY1
through transition between the standby state STBY1 and the standby
state STBYn.
[0112] In this way, in Embodiment 2, the transfer-enabled number Na
is adjusted utilizing transition between the transfer-enabled state
Act and the standby state STBY1 able to transition in the shortest
time and having highest power consumption in the case of short
cyclical load fluctuations; utilizing transition between the
transfer-enabled state Act and the standby state STBY2 having
intermediate transition time and intermediate power consumption in
the case of medium cyclical load fluctuations; and utilizing
transition between the transfer-enabled state Act and the standby
state STBYn of requiring the longest time for transition and having
the lowest power consumption in the case of long cyclical load
fluctuations, whereby responsiveness to traffic load fluctuations
can be improved and more efficient reduction in power consumption
can be achieved.
[0113] In Embodiment 2 of the present invention, the management
server 101 may also calculate the total spectrum of active circuits
from the linkup state in all of the circuits of the data transfer
control device, and employ the total spectrum of the data transfer
control device as the traffic load.
C. Modifications
[0114] While the present invention has been shown hereinabove based
on certain preferred embodiments, the invention is in no wise
limited to the is particular embodiments herein and various
modifications can be made without departing from the scope of the
invention. Possible modifications include the following, for
example.
[0115] C-1. In the preceding embodiments, the transfer-enabled
number is adjusted through transition between the transfer-enabled
state Act and transfer-disabled standby states; however, it would
be acceptable to transition among a plurality of transfer-enabled
states Act that differ from one another not only in terms of
transfer-enabled number but also in terms of capability and power
consumption for example; or a combination of transitions between
transfer-enabled states Act and standby states, and transitions
among the plurality of different transfer-enabled states Act. As a
specific example, for transfer resources with a rated processing
spectrum of 100 Gbps, it would be possible to establish a low power
consumption operating mode in which the process clock frequency is
lowered within a range in which transfer functionality may be
maintained to drop the processing spectrum to 10 Gbps, and to
transition between these states.
[0116] C-2. In the preceding embodiments, the present invention is
implemented in a data transfer control device which transfers data
using multiple retrieval/transfer resources (retrieval/transfer
portions) and which lacks a switch LSI (e.g. a crossbar switch or
shared memory switch); however, the present invention could also be
implemented in a data transfer device (or communication device)
that uses switch LSI's 135 like those shown in FIG. 14. In this
embodiment, the plurality of switch LSI's 135 correspond to the
"plurality of transfer resources" recited in the claims.
[0117] C-3. Furthermore, the present invention may be implemented
in a clustering configuration such as that shown in FIG. 15, built
from multiple data transfer control devices (or communication
devices) which are connected via a network. Clustering refers to a
technology whereby, for example, multiple communication devices are
interconnected through a network but to a user or other
communication device will collectively behave just like a single
communication device. Where clustering is implemented, multiple
communication devices can be managed just as if a single
communication device were being handled; and if one communication
device stops, it can be repaired or replaced while processing is
ongoing, without having to stop the entire system. By so doing it
is possible to reduce management load and achieve robustness to
failure through system redundancy, improving overall
performance.
[0118] In the modification shown in FIG. 15, the multiple
communication devices have on-board circuit nodes 200 for
accommodating the circuits; fabric nodes 250 for exchange of frame
data among the circuit nodes 200; and a management server 101b. The
circuit nodes 200 correspond to circuit cards on-board the
communication devices and accommodate the network circuits. The
circuit nodes 200 function as the circuit interface portions,
retrieval/transfer portions, and load distribution portions
discussed earlier. The fabric nodes 250 transfer frame data
transferred from the circuit nodes 200, to the circuit nodes 200
having the frame transfer destination ports in devices connected in
a clustering configuration. The fabric nodes 250 function as the
transfer resources discussed earlier. Depending on device
architecture, the fabric nodes 250 may also function as
retrieval/transfer portions.
[0119] In Modification C-3 of the present invention, the management
server 101b may calculate the total spectrum of active external
circuits from the linkup state in all of the external circuits in
the clustering system of the circuit nodes 200, and control the
transfer resources using the total spectrum of the active external
circuits as the upper limit. In a transfer process of the total
spectrum of active external circuits, in the event it is not
necessary to use all of the transfer resources, at least one or
more of the transfer resources can be transitioned to the standby
state with the lowest power consumption.
[0120] Furthermore, clustering systems include both shared database
type clustering systems as depicted in FIG. 16, and independent
database type clustering systems as depicted in FIG. 17. A shared
database type clustering system is a system in which multiple
servers 103s are connected to a shared database DB, with
distribution of load to the multiple servers 103s being carried out
by a load balancer. An independent database type clustering system
is a system in which the multiple servers 103s are connected
independently to databases DB, with distribution of load to the
multiple servers 103s being carried out by a load balancer. In this
embodiment, the multiple servers 10 correspond to the "plurality of
transfer resources" recited in the claims.
[0121] C-4. In the preceding embodiments, in an exemplary
embodiment of the plurality of standby states they include a
suspended operation state STBYn; however, it is not always
necessary to include a suspended operation state STBYn among the
plurality of standby states, and it would naturally be possible for
the invention to be utilized in an embodiment that assures
redundancy, such as shown in FIG. 18. The present invention could
also be implemented in a data transfer control device
(communication device) in which link aggregation has been
implemented as shown in FIG. 19.
[0122] Link aggregation is a technology for virtual bundling of
multiple physical circuits and treating them just like a single
circuit. An example is the IEEE P802.3ad standard. Where link
aggregation is implemented, it will be possible to use a spectrum
equal to the sum total of the specified spectra of the physical
circuits. For example, through virtual bundling of five 1 Gbps
circuits, it is possible to use a virtual communications spectrum
of 5 Gbps. Advantages of link aggregation are that it is possible
to expand the communications spectrum without the use of high-speed
circuits; and that in the event of a problem on one of the physical
circuits, communication can continue uninterrupted using the other
circuits.
[0123] C-5. In the preceding embodiments, distribution of load was
carried out, for example, according to the communication data
classes (communication classified by specific rules) of "multicast
communication (specific communication)" and "unicast communication
or other non-multicast communication (normal communication)";
however, as shown in FIG. 20 it is possible for the purpose of more
efficient and stable communications to implement the present
invention in conjunction with an arrangement whereby data is
distributed according to the individual communication data classes,
distributing only the load of a single communication data class to
the transfer resources.
[0124] Load distribution involves allocating transfer resources to
"multicast communication" and "non-multicast communication" as well
as distributing data according to its communication data class;
however, other classifications are possible provided they are based
on communication data classes, and three or more classifications
would be acceptable as well. Specifically, it is sufficient for the
plurality of transfer resources to be assigned individually to a
plurality of pre-classified communication data classes in an
arrangement whereby the load distribution portions analyze which of
the multiple communication data classes was used for communicating
the input data and distribute the analyzed data to the transfer
resource to which the communication data class of the analyzed data
was assigned.
[0125] By so doing it is possible to increase process efficiency
and stability by narrowing down the communication data classes
targeted for processing by the transfer resources. Furthermore,
where combined with Embodiment 2, the cycles of each of the
individual classified communication data classes can be utilized to
enhance the control rules, and achieve both reduced power
consumption and a stabilized data transfer process.
[0126] Furthermore, with an arrangement focused on communication
data classes, it is not always necessary to assign multiple
transfer resources on the basis of communication data class;
control rules can be enhanced by focusing on both communication
data class and load cycle. For example, since the cyclical nature
of communication and the importance of communication differ between
data communication by telephone and other kinds of communication,
where control is possible through focus on communication data class
and cycle in this way, it will be possible to provide a control
device that more closely meets user needs.
[0127] C-6. In the preceding embodiments, load prediction was
carried out on the basis of the cyclical nature of the load;
however, it would be possible to make a prediction on the basis of
an increase in load due to a non-regular event such as the World
Cup or the opening of the high school baseball season (opening day
is different each year), for which it is difficult to predict
increased load based on periodic nature (season) alone, but which
is nevertheless a scheduled event that is known in advance. In this
way, fluctuations in load may be predicted on the basis of
information representing predicted load fluctuations that have been
predicted in advance outside the network transfer system 100.
[0128] Specifically, the management server 101 may be provided with
a memory area, not shown, having an event calendar (load prediction
information) stored therein; and load may be predicted on the basis
of this event calendar. The present invention is applicable to
instances in which load is predicted by any of various methods: for
example it would be acceptable to predict load fluctuations on the
basis of the rate of change of load; or to compile a database of
load fluctuation patterns and to activate extra transfer resources
in response to detection of an unknown fluctuation pattern.
* * * * *